The present invention relates to a golf club head having a hollow structure comprising a metal member and a resin member and a method for manufacturing the same, more particularly to a welding technique for joining a resin member and a metal member without using an adhesive agent.
In recent years, a golf club head having a hollow structure manufactured by joining two or more members has been proposed.
The following patent document 1 discloses a metal golf club head formed by welding a head main body made of a metal material and provided in a crown portion with an opening, and a crown member made of a metal material and covering the opening.
The following patent documents 2 and 3 each disclose a hybrid golf club head comprising a head main body made of a metal material and provided in a crown portion with an opening, and a crown member made of a resin material and fixed to the head main body by means of an adhesive agent so as to cover the opening.
In the golf club head disclosed in the patent document 1, all of the members are made of metal materials, therefore, the total mass of the club head tends to increase, and it is difficult to increase the volume of the head within a limited range of the total mass.
In the hybrid golf club heads disclosed in the patent documents 2 and 3, owing to the crown member made of a relatively light resin material, the total mass of the club head may be reduced. But, the bonding strength between the crown member and the head main body tends to become relatively low due to the adhesive agent. Thus, there is a problem with the durability.    Patent document 1: Japanese Patent Application Publication No. 2007-125242    Patent document 2: Japanese Patent Application Publication No. 2007-229002    Patent document 3: Japanese Patent Application Publication No. 2009-183620